import math

numbers = "12952397350"
print("我的手机号是：" + numbers)  # 我的手机号是：12952397350

my_phone = numbers
print(my_phone)   # 12952397350

# print = '123'
# print(print)
"""
报如下错误：
Traceback (most recent call last)
TypeError: 'str' object is not callable
"""

print(math.log2(8))  # 3.0

a = -1
b = -2
c = 3

print((-b + math.sqrt(b ** 2 - 4 * a * c)) / (2 * a))
print((-b - math.sqrt(b ** 2 - 4 * a * c)) / (2 * a))

# type()  获取类型
print(type("字符型"))   # <class 'str'>
print(type(6))   # <class 'int'>
print(type(6.0))   # <class 'float'>
print(type(True))   # <class 'bool'>
print(type(None))   # <class 'NoneType'>

x = 1.99E1413
print('科学计数法：', x, 'x的数据类型：', type(x))      # 科学计数法： inf x的数据类型： <class 'float'>

print(0.1 + 0.2)        # 不确定尾数问题   0.30000000000000004
print(round(0.1+0.2, 1))   # 0.3


